Niemann-Pick disease type C or Gaucher's disease type 3? A clinical conundrum

We describe a patient who presented with a neurovisceral syndrome characterised by ataxia, bulbar dysfunction, supranuclear gaze palsy, splenomegaly and foamy histiocytes in the bone marrow. This presentation was suggestive of a lysosomal storage disorder such as Niemann-Pick disease type C or Gaucher's disease type 3. We review the presentation of these disorders, with a focus on the neurological features. In addition, we briefly discuss the disease-modifying therapeutic options which have recently become available.